Breakaway mounting tabs on the woofer frame allow the TR400-CXi to be installed in four-hole or two-hole configurations. Injection-Molded adaptor plates are also included to allow mounting of the TR400-CXi speakers into a 4 x 6 (100 x 150 mm) speaker location.

Tweeters are coaxially mounted and built with 0.5-inch textile diaphragms that deliver clean response, on and off axis. The small size of the TR tweeter minimizes tweeter protrusion, allowing TR coaxials to fit behind most factory speaker grilles.

Speaker grilles are included, each consisting of a black grille tray with satin silver accents and a black steel mesh grille with an electroformed JL Audio logo.